DE 199 19 783 A1 describes a manufacturing method for deep-drawn sheet metal composite parts with at least two layers. The adhesive used for this purpose in particular is an epoxy hot melt adhesive that is partially crosslinked by application of heat at a specific temperature and then formed after cooling down, and finally the crosslinking is completed by another application of heat. However, this method has the considerable disadvantage that it is very difficult to control the extent of partial crosslinking. We can also expect that during long storage times, such a partially crosslinked part will crosslink further so that after a long storage period, forming is no longer possible or else can be done only very poorly.
WO 00/21747 describes a method for fabrication of a baked enameled molded component. A hot melt epoxy adhesive is used for this purpose, which is crosslinked after deep drawing by application of heat. However, the described method leads to poor adhesion, which is why it is necessary to use a primer. Also the cooled hot melt adhesive cannot be plastically shaped and so during forming, in particular during deep drawing, leads to cracks in the molded part.
EP 0 343 676 A2 describes a reactive hot melt adhesive based on a polyurethane-epoxy adduct for use as a hem flanging adhesive in automotive assembly. But according to this method, folding is done immediately after sticking together the steel plates. However, the disclosed adhesive cannot be used for fabrication of a storable semifinished product, since the strength achieved (10 psi) is too low to prevent the adhesive from being squeezed out from between the plates by compressive forces during storage or during other forming methods.